Very interesting effect and excellent use of desat. A variation on this idea is to have had only a single place for the eye to land and that is the instrument, by toning down the the left hand. Nevertheless, the instrument is coming right out and the background is great. Bumping up to 7
I don't know is this is stopped motion or not - but the image is absolutely wonderful with the bright brown violin contrasting with the shades of gray throughout the rest of the image. The composition is super. I'd give it an even higher rating if it was for a "3 Cs" challenge (color, contrast and composition). There's humour somewhere in there. Anyway, if you don't mind, I'll make this one of my "favorites". Good luck with the challenge.
Two things that I think might hurt you here: this is very slow motion and selective desat might be a little overdone lately. However, for me, both are working very well. This is a unique image that is well done in this challenge, and it really stands out in my mind. Very nice, with perfect DOF and just a few very bright highlights.
This is a beautiful shot but I fear it will suffer because there is no way to know if this person is, in fact, in motion. I will give it the benefit of the doubt. 7. Good luck.